The goal of this project is to develop a robust MRI protocol for detection and monitoring of grafted Mesenchymal Stem Cells (MSCs) in bone tissue. It has been shown that MSC's have great potential for treatment of bone disorders such as osteoporosis and bone fracture. Success of MSC therapy largely depends on the number of MSC on the bone surface. Our collaborator from UC Davis has developed a novel method to considerably increase the homing and osteogenic differentiation of MSC's on the surface of bone. However, further progress in this promising area of research is required on in vivo technique to observe the grafted cells overtime. Researchers from University of Minnesota (our second collaborator in this project) developed a new MRI pulse sequence, which is able to image ultra-fast relaxing spines. In this project we will implement this new imaging technique to detect therapeutic MSCs in bone tissue. We will develop MSCs labeling procedure and SWIFT acquisition protocol for in vivo detection of grafted MSCs in bone tissue. With help of SWIFT pulse sequence it would be possible to generate a positive MR signal from iron labeled cells, which was not conceivable with traditional MR imaging. The proposed method will be very useful in all areas of stem cell therapy and have a profound impact on stem cell treatment of bone degenerative diseases and fracture repair.